The present invention relates generally to data input devices and, more particularly, to data input devices adapted for use with portable communications and computing equipment.
Demand for compact communications and computing equipment has increased dramatically over the last decade. Computers that can be held in the palm of your hand and wireless phones that fit in a shirt pocket are two examples of popular miniaturized machines. More recently, demand for wireless e-mail and Internet access has begun to soar, with experts projecting future demand to rise at unprecedented rates.
One problem associated with miniaturized communications and computing equipment is having a convenient way to input data, such as character and pointing device data, into such equipment. Early miniaturized computing equipment, typical of the 1990s, included a miniaturized keyboard that was scaled to fit the desired sized of the computing equipment. Typing a few words using such systems is quite laborious because the operator""s fingers are typically too large to use the device as a traditional keyboard. Portable communication equipment, on the other hand, typically include a conventional 12-button keypad to input data. It is extremely difficult to use this set-up to enter non-numerical data. For example, to enter the word CALL, an operator would hit the button marked xe2x80x9c2-A-B-Cxe2x80x9d three times for C, the button marked xe2x80x9c2-A-B-Cxe2x80x9d once for A, the button marked xe2x80x9c5-J-K-Lxe2x80x9d three times for L, and finally the button marked xe2x80x9c5-J-K-Lxe2x80x9d three times again for the final L.
To ease the problem of character input, some manufacturers of both communications and computing equipment have recently developed pen-type portable devices in which a real keyboard or keypad is not provided and data input operations can be carried out by utilizing a miniaturized virtual keyboard displayed on a touch sensitive screen. The pen can also be used as a pointing device to select items on the screen. An additional feature of many touch sensitive screen systems is the ability to write characters with a pen or stylus that is recognized as individual characters by the device. Another recent development is the collapsible keyboard, such as those currently being marketed by Palm Computing. This keyboard may be folded and carried in a briefcase or even a pocket, and is opened and plugged into the miniaturized equipment before it is ready to use. Yet another development is voice recognition. However, this technology is not currently highly reliable and, as a result, input errors are common. Furthermore, numerous circumstances arise where voice input is not practical or appropriate. Moreover, voice recognition is not suitable for entering pointing device information.
While each of these methods represents a form of improvement over previous technologies, the need remains for a data input device for use with miniaturized communications and computing equipment that allows an operator to easily input characters and data into such equipment. Preferably, such an input device would incorporate wireless techniques to sense the position and motion of the operator""s fingers to allow the user to enter data without the use of a physical keyboard or a pointing device.
A data input device having these desired features has now been developed. Broadly speaking, the data input device of the present invention optically interfaces with an operator to detect the position of objects within a particular input zone, e.g., an area defined as a xe2x80x9cvirtual keyboardxe2x80x9d in which the operator may interact to enter character data into associated computing equipment. Preferably, the objects are the operator""s fingers placed within the input zone. As a character input device, each character data corresponds to a unique arrangement and position of the objects within the input zone. As a pointing device, the relative motion of the operator""s fingers defines the input area. The input device includes a source of optical sensor light illuminating the input zone with sensor light. The source of optical sensor light may be ambient light surrounding the operator or a light emitting device adapted to emit light in a direction toward the operator""s fingers. Preferably, the source of optical light covers the input zone. The sensor light reflects off the objects in a direction generally toward the input device. The data input device also includes an optical detector arranged to receive the reflected sensor light as a reflected light pattern representing the relative position of the operator""s fingers within the input zone. The optical detector converts the reflected light pattern to an electrical signal representing the particular character data desired to be entered by the operator. A microprocessor then receives the electrical signal and correlates the electrical signal to character or position/motion data.
In one embodiment of the virtual data input device, an image generator is used to project an optical image that represents character data, e.g., an image of a real keyboard. The image generator may be formed by an optical element, such as a stencil, mask, holographic element, mirror array, or other suitable device known in the art of image projection, designed to allow light to pass through portions of the optical element and a light generator positioned to emit visible light through the portions of the optical element, whereby the light passed through the optical element forms the optical image.
The present invention also includes a novel method to enter character data into communications or computing equipment based on the position of objects within an input zone, e.g., an operator""s fingers on a virtual keyboard. The position of the objects within the input zone uniquely corresponds to particular character data. A reference position is established to associate an initial position of the objects within the input zone and to associate a plurality of positions of the objects within the input zone to unique character data. A source of optical sensor light is provided to illuminate the input zone such that the sensor light reflects off the objects. The reflected sensor light is then received as a reflected light pattern representing the position of the objects within the input zone. The reflected light pattern is converted to an electrical signal that is then correlated to the unique selection of character data, which may then be input into the electronic equipment.